VIBRATIONAL POPULATION IN FEMTOSECOND UV LASER-DESORPTION OF NO FROM NIO(100)

We have investigated the internal state populations of NO molecules de sorbed from an epitaxial film NiO(100)/Ni(100) at 100 K. After desorpt ion with a 550 fs pulse at lambda = 314 nm (h nu = 3.9 eV) the molecul es have been detected using (1 + 1)-REMPI via the A(2) Sigma(+) (nu' = 0,1,2,3)<--X(2) Pi(nu '' = 0,1,2,3) gamma-band transitions. The vibra tional states nu '' > 0 are highly populated approaching vibrational t emperatures of 3800 K. The results are compared with the data obtained for the same system with nanosecond desorption pulses at h nu = 6.4 e V.